Induction coil



Nov, 20 1923.

. A. A. KENT INDUCTION COIL Filed June 25, 1921 2 Sheets-Shet 1 Nov. 20 1923.

A. A. KENT INDUCTION COIL Filed June` 25, lSZl 2 Sheets-Sheet 2 IN VE N TOR. M M

@fm/M @M ATTORNEY.

Patented ov. 20, 1923.

UNITED STATE/s PATENT oEElcE.

ARTHUR ATWATEB KENT, F ABDMQBE, PENNSYLVANIA.

I INDUCTION coIL.

.Application IdI June 25,

T o aZl wzo-m. it may concern:

Be 1t knownl that I, ARTHUR ATWATER .KENL a citizen of the United States, re-

' siding in Ardmore, county of Montgomery,

and State of Pennsylvania, have invented certain new Iand useful Improvements in Induction Coils, of which the following is a specification. l.

. Myinvention relates-,to induction coils, and more particularlyY to those suitable for producing the ignition sparks in internal `combustion engines, such as employed upon motor vehicles or the like.

My invention residesa in vinduction coil structure wherein electrical connection vbetween a winding of the induction coil, as, the secondary winding, and a terminal is effected by connecting the windingto a core member of subdivided magnetizable material and completingv the connection to the terminal by a conducting pin` rod or the like extending into the subdivided core and connecting with the terminal.

My invention resides also in an induction coil comprising primary and secondary windings housed within a casing and provided with an external core structure of Subdivided magnetizable material disposed b e- .tween the casing and the'winding structure,

the outer core material being ununiform or eccentricas regards distribution around the coil windings. f

My invention resides further in inductign coil structure of they characterhereinafter described provided with means for facilitating transfer or radiation 'of heat developed thergin.

Figs

" fied coil structure.

Fig: 6 is a sectional view on the line 6-6 of Fig. 5;

Referringto Figs. 1 and 2, C is the inner core composed of numerous iron .wires substantally parallel with each other and e011-,

4 and 5 are side elevations of a modii L1921. aerial No.. 480,316.

fined in Aa bundle, as byfia surrounding spool or wrapping a, preferably of insulating material. Surrounding lor wound upon' the member a is the secondary coil or winding S formed in any suitable way, asby alternate layers of small insulated wire or cony ductor and paper or other ,insulating ma? terial. T he secondary coil S may be wound upon the member a or' Imay be wound separately as a unit and then slipped over the tube or member a to the position indicated.

Insulated from and surrounding the second- 'ary winding S isthe primary coil or vvind ing P of relatively coarser wire and fewer turns, which may .constitute a unit with the secondary S or may be separatelywound and placed ingthe positionA indicated. A s shown, the Aprimary P may have greater longitudinal' extent than the secondary'S,

the core C preferably being longer than either primary or secondary winding. The

induction coil structure comprising the core C and the primary and secondaryY coils P and S is placed within a casing preferably of metal, having the bottom closure' 'member b, also preferably of metal. Secured to the casing or housing member H at its lower end is the base member c having the 2 upstanding flange d secured to the housing or casing-H in any suitable) manner. The base flange c may be provided with holes .ethrough which screws or other fastening means may extend. The induction coil structure preferably rests at its lower end upon insulating members, as a sheet of mica f resting in turn upon disks g, of insulating materiau in turn resting upon the bottom member b. Surrounding the primary P is preferably provided the sheet of insulating material h.

To facilitate and cheapen the introduction and placing ofthe iron or other wires, of an external core' structure, without, however,

'detracting materially from the electrical and magnetic characteristics of the inducs tion coil, and in some casesJ even improving the characteristics, the structure comprising the inner core vC and the primary and secondary windings is displaced laterally, as'indicated in Figs. 1 and 2, preferably to the extreme position where, as indicated', the outer winding is disposed immediately adjacent the casing In the example illustrated, this leaves a crescent-shaped gap between the inside of the casing H and the winding ilo structure, into which space arethen introl duced, preferably fillingsuch space, numerous parallel iron wires forming the external core structure E, which with the i inner core C forms part. of the magnetic circuit of the induction coil. By so dissing the winding structure and the external core wires, the latter are more easily and quickly, and therefore cheaply, placed in position than in the case where the winding structure is placed substantially co-axial with the housing or casing H and the external core structure made of substantially uniform' thickness entirely surrounding the winding structure, as indicated, for example, in my` copending application Ser. `,No

The' core structure EV as herein provided serves also to conduct yheat from the winding structure, particularly the primar winding P, to and through the casing Upon the exterior of the casing H, preferably'throughout or at least in part within the longitudinal vextent of the primar 'coil P,-or (and) external core E, is app ied a plurality of metallic heat radiating memers each comprising the cylindrical flange z' in good heat conducting contact or rela- .tion' with the casing H and the outwardly extending flange j. These heat conducting or radiating members in the example illusl trated are similarpto the above described base member c with its upstanding flange d.

A. Such heat'radiating structure is of particular advantage in an induction coil in which the primary winding surrounds the secondary and in which the housing or casing H is metal, and particularly when an external corew structure is employed which,

however, may or may not, as desired, be eccentric or non-uniform as herein shown.

Closing the other end of the casing -H is a cap A of molded insulating material, as condensite, bakelite orother suitable material. In the example illustrated the cap A is secured to the casingl H by pins or screws k. The cap A, in the example illustrated, has a central inside recess m, and

metallic insert or secondal co-axial with such recess the cap is yprovided with a boss n within which is molded the which enga es any )suitab e conductor, as a flexible cab e, connecting to the distributor -cap A in position as indicated. a metal nail,

pin, rod or other member` N is inserted through the hole g in the insert vo and aligned holen in the material of thecap lAand terminal 0, with or insert o. s

This structure affords a simple and ex- -tremely cheap mode of connecting an end of the secondary winding to the secondary terminal of the' induction coil. The conncction at p to the core C is made before the core C and winding structure are introduced into the casing H; such connection maybe made, for example, at the time the core wires C are introduced into the spool or tube A, or at the time the secondary winding S is wound upon the tube a in which may have previously'been placed the wires of the core C. The final connection to the terminal o is then made at any later time when the cap A is applied to the casing H after previous introduction of the core C and the winding structure.

The connector-N is preferably provided with a head 7'. Above the member N, or its head 1 if provided therewith, is disposed a cup-shaped cap or member s forced downwardly inr the bore of the terminal 0 to position indicated to confine the conductor or connector N in its operative position indicated.` .A

The other end of the secondary winding S may be connected to the inner end of the primary P and both connected by conductor t with the terminal or metallic insert u molded in the cap A and threaded to receive a binding' screw e. The other-or outer end of the primary P is connected by conductor fw to the metallic terminal or insert 1/ molded in the cap A and threaded to receive a binding screw z. For one of the various modes of connecting the induction coil structure in an ignition circuit, reference may be had to Fig. 3, wherein a battery `Yor other source of current B has one of its terminals connected to ground or conducting frame G ofthe engine or motor vehicle, or to a return conductor. The other terminal of the source B is connected through ignition switch a1 with ,one or the other of the terminals or Yinserts u or y above described. In the example illustrated the connection is made to the terminal u, and from the other primary terminal y connection isv made to one of the co-operating interrupter contacts b1, c1, one of which is actuated by the usual timing cam d1, driven in definite relation with and by the engine shaft. One of the interrupter contacts is connected to ground `or return conductor G, and shu ting the contacts is the usual condenser rlhe secondary terminal o is connected b conductor el, as` the above mentioned exible conductor or cable, to thexotary distributor llt) contact f1 also rotated b 'fand in definite relation with the engine s aft and co-acting in'succession with 4the stationary terminals g1. connecting` respectively. with the Spark shown as provided with heat conducting or radiating struc-ture comprising the saddle il attached to the metal casing H and having -tlie outwardly extending lieatconducting or radiating extensions j1 terminating in outwardly tui'ned flanges k1, also serving as means for conducting or radiating heat rom the coil structure. The flanges It" may be provided with holes m1 through which may extend screws or any othersuitable fastening means n1 for securing the flanges L1 to anyv suitable support, as o, which may be of nietal, wood or other suitable material, and when of metal assists in conducting heat away from the coil structure.

This` heat conducting or radiatingstructure is also preferably located, at least in part, within the longitudinal extent of the primary P or external core E, though it will be understood, asin connection with the structure i', j of Fig. l, that the structure may extend throughout the entire longitudinal extent of thel primary P or' external core'E, or may be disposed beyondthe primary P or core E, or in fact, in any suitable relation upon the casing H.

Vhen employing the heat transfer structure indicated in Figs. 4 6, the casing4 lH may terminate at its lower end in a simple metallic bottom member rp1 the members c, d of Fig. 1 in this instance being omitted.

1. Induction coil structure comprising a coreconsisting of a bundle of substantially parallel wires, primary and secondary windings, aconnection from sad`secondary winding tov said core, a member of insulating material, a secondary terminal carrie thereby, and means for connectin said termiual `with said. secondary win ing. comprsing a member carried by and electrically connected with said terminal and projecting therefrom between said `core wires.

2. Induction coil structure comprising a,

core consisting of a bundle of substantialliy parallel wires, primary and secondary win ings, a connection from said secondary winding to said core, a member of insulating material, a secondary terminal carried thereby and having a perforation, and means fork connecting said terminal with said secondary winding comprising a conductingmember carried by and contact' with said terminal and projectthro said core tween the wires thereof and contactmg with said wires.

3. Induction coil structure comprising a core consisting of a bundle of .substantially rforation into and terminating in said.

said secondar parallel wires, primary and secondary wind: ings, a connection from said secondary winding-to said core,'a member of insulating material, a secondary terminal carried thereby and having a perforation, an elongated conducting member having a head and a shank projecting `through said perforation into and terminating in said core between tlie wires thereof and contacting therewitli,*and means co-acting with rsaid ter-` niinal and the liead of said conducting meinber for holding said contacting member in position.

,4. Induction coil structure. comprising a core consisting of a bundle of subst-antially parallel wi-res, a secondary winding surrounding'said core, a connection from said secondary winding to said core, an enclosing casing, a cap of insulating material forming a cosure for said casing. a secondary terminalon said cap, and a 'cony ducting member carried by and connecting with said terminal and project-ing therefrom into `and terminating in said core between said wires and contacting therewith.

5. Induction coil structurev comprising a core consistingof a bundlev of 'substantially parallel wires, a secondary winding surrounding said core a connection from the inner layer of said secondary windingH to said core, a primary winding surrounding said secondary winding, a casing enclosing said core and windings, a cap of insulating material forming an end closure for said casing, a secondary terminal carried by said cap and having a. perforation, and a conducting member carried by said terminal projecting through said perforation into and terminating in said core between the wires thereof and contacting therewith.

wlnduction coil structure comprising an inner core, primary and secondary windings surrounding said core, an enclosing housin and a straight external core having its en spaced from .saidinner core and comprising divided magnetizable material disposed between said windings and said casi in a mass diminishing in thickness aroun said windings. l f

7 Induction coil structure comprisin an inner core, primary and secondary win Y ings disposed one upon the other around said core, an enclosing ousing, the outer winding disposed eccentrically within said cas,y ingsand a straight external corev having its en spaced from said linner core and comprising subdivided magnetizable material disposed in the space etween said outer winding and said 8. Induction coi structue comprisingan inner core, a secon ary win ing s un ing said core, a.y p winding suuirrgunding winding, an enclosing casing, said core Y windings disposed eccentrically within said casing with said primary casinghsaid core and windings winding closely approaching. said casing on one side whereby there is left a space of crescent form between said primary Winding and said casing, and an external core comprising subdivided magnetizable material disposed in said space. l

9. Induction coil structure comprising an inner core, a secondary winding surrounding said core, a primary winding surrounding said secondary Wmding, an enclosing centrically within -said .casing with said Yspace of crescent form between primary winding closely approaching said casing on one side whereby there islleft a said primary winding and said casing, and an external core comprising substantially paral lel wires disposed in and substantially illingsaid space.

10. Induction coil structure comprising a metallic casing, core structure and windings within said casing, and a heat radiating structure comprising heat radiating meming said casing and 'lng members on the exterior lextending substantial] casing and in heat con ucting relation therewith, and an integral outstanding vmetallic casing,

bers spaced longitudinally of and surroundin heat transfer ,relation therewith.

11. Induction coil structure comprising a metallic casing, core structure and windings within said casing, and heat radiating structure comprising a plurality of heat radiatof said casing, each of said members comprising' a flange parallel with ASaid flange. 12. Induction coil structure coniprismg a disposed ec-' 1921. a core, a'ysecondary windlng` surrounding said core, a primary winding `between the ends Yof said primary winding.

between the ends of said external core.

14. Induction coil structure comprising a metallic casing, a core, a secondary winding surrounding said core, a primary winding surroundin said casing anddisposed at least in part between the endshofsaid` primary winding'. 15. `Induction coil structure comprising a metallic casing, a core, a secondary winding surroundingysaid core, a primary winding surrounding said secondary winding, an` external core between said primary windin and said casing and in contact with sai members on said. casing, at least some of said members located said secondarywinding, and a i' 'heat radiating structure upon the exterior of casing7 and heat radiating structure u on i the exterior of said casing least in part between ternal core.

In testimony whereof I have hereunto and dispose at the ends of said exf ailixed my signature this 23rd day of June,

ARTHUR A'rwarna KENT. 

